The invention relates to a blocking device for a cylinder lock with a stator, a rotor rotatable in this stator by means of a key, an additional blocking element which can linearly engage and disengage the rotor along a displacement axis, and an electrically driven control means for actuating this blocking element, with the control means comprising a rotating driven end of the shaft, a helical drive unit, which is disposed between the control means and the blocking element, as well as an electric control device for generating control signals for the control means and a method for operating this device.
Blocking devices of this type are applied in locks, in particular in cylinder locks. In the case of cylinder locks it is known to provide mechanically coded tumblers between rotor and stator and additionally a mechatronic blocking device which blocks the rotor independently of the mechanically coded tumblers. Through this combination of mechanically coded tumblers with an electric or electronic coding, the security and adaptability of such locks or locking devices can be considerably increased. Such locking configuration is known for example from EP A 730 073. This locking device comprises in known manner a rotatable rotor, wherein this rotor is provided with a key channel, into which a flat key can be inserted. This flat key comprises on the key bit in a manner known per se mechanical codings, which cooperate with tumblers between rotor and stator. With the correct coding of the key, these mechanical tumblers can be unblocked and thus the mechanical portion of the locking device can be moved into the opening position. The key comprises additionally an electronic coding, which, in this example, includes a transmitter for information signals. As a counterpiece on the cylinder lock a receiver is disposed which receives the information signals transmitted from the key and supplies them to an electronic processing device. This electronic device controls an additional electromechanical latch whose blocking part can engage and disengage the rotor. This electromechanical latch comprises an actuation component or a control means for the blocking part. The control means can be known means for generating translational motions, for a example a magnetic drive or a rotating setting drive. In order to hold the blocking part in the blocking position and to secure it against unauthorized interference from the outside, a reset spring is available which presses the blocking part in the direction of the rotor. This is especially necessary in the case of blocking parts which are moved translationally by solenoid magnets, since here in the de-energized condition the control means does not exert any forces onto the blocking part.
The above described and further known locking devices with cylinder locks, which comprise, on the one hand, a purely mechanical coding and, on the other hand, an electronic coding with additional mechanical blocking elements, for their orderly actuation or unblocking, a mechanically correctly coded key and an electronic module on the key, which exchanges information signals or data with an electronic module in the cylinder lock. This data exchange can take place through direct contact elements or free of contact via a transmitter-receiver system. If the electronic module on the key contains the correct data, the electronic module in the cylinder lock accepts this key as being authorized for opening and releases the additional blocking device. In spite of this twofold coding and increased security, the known electromechanical or mechatronic locking devices which can still be interfered with sufficient expenditure through magnetic forces, vibration or impacts or by combinations thereof.
In borderline cases this can lead to the fact that such a locking device can also be opened without authorization without keys with matching electronic coding. Of disadvantage with locking devices with cylinder locks of this type and with an additional electronically controlled blocking element is also the fact that the additional blocking element and the corresponding control means, have dimensions, in particular with the actuation by a solenoid magnet which are greater than the normal housing of commercial cylinder locks. Therefore additional housings are necessary and the corresponding locking devices cannot be applied in standardized, normally utilized lock boxes on doors or other objects. In order to make installation possible additional adaptations and changes are necessary.
In the mechanical coded cylinder locks, which are used for example with rotary grip locks or cylinder olive-shaped handles for rotary rod locks, it is known that the structural dimensions can be reduced if the blocking element is actuated via a helical drive unit. These known actuations of blocking elements through helical driving however, are not able to solve the problem of unauthorized unlatching by actions from the outside. WO 98/28508 discloses a solution which essentially employs an additional electromechanical latch, such as is described in EP A 730 073, in which inter alia for generating the movement of the blocking element a control means with different types of helical driving is proposed. In order to counteract unauthorized interference from the outside onto the blocking element, additionally reset means and/or force transmission means are necessary, which are said to counteract or neutralize forces potentially applied from the outside. These reset and force transmission means are essentially disposed on the control means approximately at right angles to the longitudinal axis of the threaded drive, whereby either radially or parallel to the longitudinal axis of the cylinder lock additional space is required. This device can therefore also not be installed into the housing of normal cylinder locks, but rather additional annular housing or longitudinal housing components are necessary.
Due to the large number of requisite parts and their differing axes of action, the assembly and installation of this blocking device is complicated and costly and often requires additional adaptations in the installation region into an object, for example into a lock box and/or a door.
The present invention addresses the problem of providing a blocking device for a cylinder lock with an additional mechatronic blocking device in which this additional blocking device can be installed into a standard lock housing, for example into its crosspiece, simultaneously the unauthorized unblocking through interference from the outside is virtually prevented and the additional blocking device is structured as a compact structural unit in simple manner and with a minimum number of parts. The additional blocking device for a cylinder lock is furthermore developed as a kit which makes possible the retrofitting of mechanically coded cylinder locks and it will, moreover, be applicable in different systems of cylinder locks.
This problem is solved in terms of device through the characteristics defined in the characterizing clause of patent claim 1 and in terms of method according to the characteristics of the independent method claim. Advantageous further developments of the invention are evident based on the characteristics of the dependent patent claims.
In the blocking device according to the invention the driven end of the shaft of the control means, the rotational axis of the helical drive unit, as well as the blocking element and its linear guidance are disposed on a common longitudinal axis, or these elements have a common axis. This disposition yields the advantage that these elements can be combined to form a compact structural unit and a simplified method of construction is made possible. Due to the orientation of the rotational axis of the helical drive unit toward the common longitudinal axis, the rotary motion of the driven end of the shaft of the control means can be converted directly into the linear motion of the blocking element without additional elements, such as reset means of force transmission means being necessary.
The helical groove which is disposed on a first portion of the helical drive unit, along a shell surface about the common longitudinal axis, has a positive pitch over a certain predetermined segment and forms therewith a coil-form ramp, similar to a threaded worm. The helical groove has a certain length, which with the pitch determines the linear stroke travel of the helical driving. The two end regions of the helical groove are terminated by stop faces and determine, on the one hand, the blocking position of the blocking element and, on the other hand, the opening position of the blocking element. In the blocking position the blocking element has engaged into the rotor and blocks it relative to the stator. In the opening position the blocking element does not extend into the rotor and is disengaged from it. At least at that end region of the helical groove, which determines the blocking position of the blocking element, an additional longitudinal element of the blocking groove is disposed which exhibits no pitch. This longitudinal element without pitch is in a radial plane with respect to the longitudinal axis. A slide element disposed on a second portion of the helical drive unit, which engages the helical groove, in this region of the helical groove without pitch is form-fittingly and without action of force held in the direction of the common longitudinal axis. In connection with the characteristic that either the first portion of the helical drive unit with the helical groove or the second portion of the helical drive unit with the slide element is fixedly connected with the blocking element, the advantage is obtained that the blocking element in this end region of the helical groove, i.e. in the blocking position, is also held form-fittingly and without action of force. Usefully, the second end region of the helical groove is also provided with an additional longitudinal element, which does not have a pitch. Thereby the advantage is attained that in both end positions of the helical driving the blocking element is held through an operative connection between the helical groove and the slide element, which cannot be affected through external interference from the outside. In this implementation of the blocking device, such external interference such as magnetic forces, vibrations, impacts or resonance oscillations cannot displace the blocking element from the blocking or opening position. Unauthorized actuations of the blocking device are therefore virtually impossible. If on an end region of the helical groove with positive pitch or at a longitudinal element of the helical groove without pitch, an additional longitudinal element of the helical groove with negative pitch is annexed, an additional improvement of the security results since in this case, for example during an unauthorized attempt to displace the blocking element from the blocking position into the opening position, first an oppositely directed motion would have to be generated. The linear displacement travel of the blocking element from the blocking position into the opening position, and conversely, can be adapted in extremely simple manner by changing the length and/or the pitch of the helical groove to the desired conditions. Due to the direct coupling between helical drive unit and blocking element, the stroke travel of the helical driving corresponds to the linear displacement travel of the blocking element. Since at least in the blocking position no additional holding and reset forces act onto the blocking element, this end position is determined only by the forced guidance of the slide element in the helical groove and is uniquely determined by the form-fitting holding.
The blocking device according to the invention has further advantages since the elements of the helical drive unit and their connection to the blocking element, on the one hand, and to the driven end of the shaft of the control means, on the other hand, can be implemented differently. In a first advantageous implementation, the first portion of the helical drive unit is developed on the driven end of the shaft and specifically through a cylindrical structural part, in whose outer shell surface the helical groove is disposed. The second portion of the helical drive unit is formed by an end portion on the blocking element with an inner bore, wherein the slide element is disposed on the shell of this inner bore and projects radially into the bore. The cylindrical structural part on the driven end of the shaft extends into the inner bore at the end portion of the blocking element and is guided in this bore. The slide element extends therein into the helical groove on the outer shell of the cylindrical structural part and cooperates with it. The cylindrical structural part is connected torsion-tight with the driven end of the shaft of the control means and with rotational motions of the driven end of the shaft about the common longitudinal axis the cylindrical structural part is also rotated, whereby the slide element, and therewith the blocking element, is linearly displaced in the direction of the common longitudinal axis. The end portion of the blocking element is for this purpose secured against twisting in a manner known per se such that between the first and the second portion of the helical drive unit the desired conversion of the rotary motion into a linear motion takes place. A further embodiment of the helical drive unit comprises that the second portion of the helical drive unit is formed by the driven end of the shaft of the control means, wherein the slide element is fastened on this driven end of the shaft and projects radially outwardly. The blocking element also comprises an end portion with an inner bore, with the helical groove being formed into the shell surface of this inner bore. The end portion of the blocking element is slid over the driven end of the shaft and between the shell surface of the inner bore and the outer shell of the driven end of the shaft is formed a slide guidance. The slide element engages the helical groove and with rotational motions of the driven end of the shaft the blocking element is displaced through the cooperation of slide element and helical groove linearly in the direction of the common longitudinal axis. Here also the end portion of the blocking element is secured against twisting about the common longitudinal axis so that the conversion of the rotational motion on the control means into linear motions of the blocking means is ensured. In an especially advantageous development of the threaded drive, the blocking element is developed with an end portion which has a core bore and on whose outer shell surface the helical groove is disposed. Between the core bore of the end portion on the blocking element and the driven end of the shaft of the control means a slide groove connection is developed wherein, for example the driven end of the shaft is developed as a key shaft and on the shell surface of the core bore corresponding grooves are formed out at the end portion. This slide groove connection between blocking element and driven end of the shaft permits the transmission of the rotational motion of the driven end of the shaft onto the blocking element and simultaneously the linear displacement of the blocking element in the direction of the common longitudinal axis. The end portion of the blocking element is guided in a stationary sleeve with the slide element being disposed on the inner shell of this sleeve, which element projects radially into the bore of the sleeve and extends into the helical groove on the outer shell of the end portion of the blocking element. In this embodiment the sleeve and the slide element form the second portion of the helical drive unit and the end portion of the blocking element with the slide groove connection the first portion of the helical drive unit. This embodiment has the advantage that the sleeve can be developed simultaneously as the outer housing for the entire structural unit, which comprises the control means with the driven end of the shaft, the helical drive unit and the blocking element. This makes possible the preassemble of the structural unit, which can be placed as an overall unit into a corresponding bore on the cylinder lock and in simple manner can be connected with the electric lines.
The compact type of construction of the structural unit which is formed by the control means, the helical drive unit and the blocking element, and their orientation on a common longitudinal axis permits the installation of the blocking device into the crosspiece of a cylinder lock with the conventional structural dimensions. The outer form of the housing of the cylinder lock is therein retained and the cylinder lock with the additional blocking device according to the invention can be installed into the customary installation openings on installation objects, for example a lock box. This leads to considerable simplification since, on the one hand, a cylinder lock with the blocking device according to the invention can be completely set up and produced functionally ready at the factory and, on the other hand, no additional measures are any longer necessary when mounting it at the construction site. With the disposition of the blocking device according to the invention in the crosspiece of a cylinder lock, the common longitudinal axis is oriented approximately radially with respect to the rotational axis of the rotor. On the front portion of the blocking element a blocking pin is disposed and this blocking pin in the blocking position of the cylinder lock extends into an approximately radial bore on the rotor. Since in the proximity of the crosspiece between rotor and stator normally no mechanical tumblers are disposed, the radial bore in the rotor for the extension of the blocking pin on the blocking element can readily be disposed in this region. This can be done without mechanical tumblers needing to be omitted or their function needing to be restricted. The blocking device according to the invention is thus independent within in a broad range from the system of the mechanically coded mechanical tumblers, i.e. the blocking device according to the invention can be combined with different types of construction of cylinder locks. This is made possible since all cylinder locks correspond to an industry standard and have a crosspiece projecting radially from the stator outwardly, which serves among others for the torsion-tight fastening of the cylinder lock in the structural object, for example a lock box.
The advantages of the method for operating the blocking device according to the invention comprises that the rotational motions of the driven end of the shaft of the control means can be directly converted into linear motions of the blocking means in the direction of the longitudinal axis and that onto the blocking element during the displacement process from the blocking into the opening position, and conversely, as well as in the holding positions no additional holding and/or resetting forces are exerted. This has the further advantage that the motion sequence and the method for generating the motions of the blocking element on the part of the blocking device are relatively simple and nevertheless an intervention into the motion sequence by additional forces exerted without authorization from the outside becomes virtually impossible. In displacing the blocking element into the blocking position or into the opening position it is advantageous to stop the rotational motion of the driven end of the shaft with the aid of final stops on the helical drive unit when these end positions have been reached. The stopping or the standing still of the driven end of the shaft is electronically detected via the control device and after the passage of a predetermined control time, the energy supply to the control means is interrupted. This control method has the advantage that the control means which drives the helical drive unit via the driven end of the shaft does not need to be stopped with the aid of an electronic position control, but rather the position of the helical driving controls the interruption and/or the enabling of the energy supply to the control means. The control means is advantageously supplied with energy intermittently or pulsatingly during the activated time interval. Therewith, multiple utilization and optimization of the energy source, for example of a battery, is possible, especially if the entire length of the energy supply is determined by the control device. The activation of the control device, and thus the type and manner of the enabling of the energy supply to the control means with the driven end of the shaft is activated by information signals which are transmitted from a mobile information medium to the cylinder lock. The transmission of the information or data, can advantageously take place directly via contact elements or via a contact-free transmitter-receiver system. The mobile information medium can be, for example, a key with an electronic data medium or an identification card with a corresponding data medium. In the cylinder lock or in the associated lock box an electronic data processing unit is installed as a counterpiece, which exchanges the data with the mobile information medium via direct contacts or a contact-free transmitter-receiver system, for example a radio system.